Evaluation of the Properties of SLM-Printed Lattice Structures with a View to Potential Applications in Medical Prosthetics

The human skeleton is the frame of the human body and is made up of bones of different shapes and characteristics. Some of the bones in the human body must have high resistance to static and dynamic forces. These forces are also exerted on bone replacement implants, which must have a high level of robustness. Some of the most important properties of bone material, although different in various regions of the body, are tensile and compressive strength. These properties could be tuned for prosthetic applications by using lattice structures that can be varied in shape, unit cell size, and strut thickness. One technique that could be used to fabricate such structures is selective laser melting (SLM), which builds a three-dimensional object layer by layer from a metal powder. Another major advantage of this technology is the ability to create many different shapes, as there is a high degree of design freedom. In addition, various metal powders can be used in SLM, including those that could be used for implants such as titanium. Another major advantage of this manufacturing process is the ability to easily customize the process to the size, shape, and other characteristics of the patient’s bone structure. This work demonstrates the potential to adjust the tensile properties of objects with specific external dimensions by incorporating lattice structures and tailor them. This can impact both the ultimate tensile strength and maximum elongation, providing an opportunity for future research to more accurately replicate the properties of bone material and thereby establish an additively manufacturable bone replica for stress analysis in medical and sports research. Additionally, the surface roughness Ra, which measures approximately 10 to 15 µm, did not appear to have any significant effect on the tensile strength.